This is a question we get asked a lot, surely the chimney was ok when it was used as an open fire?

Chimneys are lined for a number of safety reasons. New chimneys may require relining to suit the fuel type being used (a gas flue liner may not be suitable for other fuels). Chimney systems that predate 1965 will often require a modern lining solution for the following reasons:

• The flue may have lost integrity and can leak smoke into rooms or other part of the building
• Condensates or tar can seep through chimney walls causing staining, inside or outside of the building
• Lining with insulation included can improve the operation of the appliance and flue – particularity important when the chimney is situated on an external wall
• Defective flue systems may be eroded and rough. Thus will cause frictional resistance to the flow of the gases resulting in poor up-draught
• Large flues over 200mm, particularly ones containing voids, may affect appliance performance. Some appliance manufacturers specify smaller flues for efficient operation